First of all, Chase will likely pull your credit report each and every time you apply for a card. There are certain times you might get lucky and a lender will consolidate two pulls into one, but I think that's only happened to me once. I think there was a Frugal Travel Guy post recently that talked about the "90 day rule" being more about organization at this point, rather than a way to consolidate multiple pulls into one.

To get to your question-- Southwest, United, and British Airways are not ultimate rewards cards. They are co-branded, so you will get points with that individual partner. Sapphire Preferred is the only one you mentioned that will get you Ultimate Rewards points.

Lastly, I would not recommend trying to get more than two Chase cards at a given time. The likelihood you actually get three approved at once is very little. Not to mention there's really little rush to get some of these Chase cards - they aren't churnable (the deals are generally one per customer for life, unlike a lot of AmEx cards where you can get the deal two years after you cancel) and I highly doubt any of them are going away very soon.

If it were me I would decide what I'm flying in the near future and what my mileage needs are. If you don't care, you may as well get the Southwest card since the deal is up to 50k points again. Throw in Sapphire Preferred's 40k+dividend+spending bonus and you're probably looking at 100k Southwest points by the end of the year if you transfer the UR points to Southwest RR points.